diff options
| -rw-r--r-- | src/backend/storage/buffer/bufmgr.c | 30 | ||||
| -rw-r--r-- | src/backend/storage/buffer/localbuf.c | 67 | ||||
| -rw-r--r-- | src/include/storage/buf_internals.h | 2 |
3 files changed, 51 insertions, 48 deletions
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c index 2362423b89d..1c3dec487a1 100644 --- a/src/backend/storage/buffer/bufmgr.c +++ b/src/backend/storage/buffer/bufmgr.c @@ -636,20 +636,7 @@ ReadRecentBuffer(RelFileLocator rlocator, ForkNumber forkNum, BlockNumber blockN /* Is it still valid and holding the right tag? */ if ((buf_state & BM_VALID) && BufferTagsEqual(&tag, &bufHdr->tag)) { - /* - * Bump buffer's ref and usage counts. This is equivalent of - * PinBuffer for a shared buffer. - */ - if (LocalRefCount[b] == 0) - { - if (BUF_STATE_GET_USAGECOUNT(buf_state) < BM_MAX_USAGE_COUNT) - { - buf_state += BUF_USAGECOUNT_ONE; - pg_atomic_unlocked_write_u32(&bufHdr->state, buf_state); - } - } - LocalRefCount[b]++; - ResourceOwnerRememberBuffer(CurrentResourceOwner, recent_buffer); + PinLocalBuffer(bufHdr, true); pgBufferUsage.local_blks_hit++; @@ -1688,8 +1675,7 @@ ReleaseAndReadBuffer(Buffer buffer, BufTagMatchesRelFileLocator(&bufHdr->tag, &relation->rd_locator) && BufTagGetForkNum(&bufHdr->tag) == forkNum) return buffer; - ResourceOwnerForgetBuffer(CurrentResourceOwner, buffer); - LocalRefCount[-buffer - 1]--; + UnpinLocalBuffer(buffer); } else { @@ -3982,15 +3968,9 @@ ReleaseBuffer(Buffer buffer) elog(ERROR, "bad buffer ID: %d", buffer); if (BufferIsLocal(buffer)) - { - ResourceOwnerForgetBuffer(CurrentResourceOwner, buffer); - - Assert(LocalRefCount[-buffer - 1] > 0); - LocalRefCount[-buffer - 1]--; - return; - } - - UnpinBuffer(GetBufferDescriptor(buffer - 1)); + UnpinLocalBuffer(buffer); + else + UnpinBuffer(GetBufferDescriptor(buffer - 1)); } /* diff --git a/src/backend/storage/buffer/localbuf.c b/src/backend/storage/buffer/localbuf.c index 6f9e7eda57c..940b80d165e 100644 --- a/src/backend/storage/buffer/localbuf.c +++ b/src/backend/storage/buffer/localbuf.c @@ -137,27 +137,8 @@ LocalBufferAlloc(SMgrRelation smgr, ForkNumber forkNum, BlockNumber blockNum, fprintf(stderr, "LB ALLOC (%u,%d,%d) %d\n", smgr->smgr_rlocator.locator.relNumber, forkNum, blockNum, -b - 1); #endif - buf_state = pg_atomic_read_u32(&bufHdr->state); - /* this part is equivalent to PinBuffer for a shared buffer */ - if (LocalRefCount[b] == 0) - { - if (BUF_STATE_GET_USAGECOUNT(buf_state) < BM_MAX_USAGE_COUNT) - { - buf_state += BUF_USAGECOUNT_ONE; - pg_atomic_unlocked_write_u32(&bufHdr->state, buf_state); - } - } - LocalRefCount[b]++; - ResourceOwnerRememberBuffer(CurrentResourceOwner, - BufferDescriptorGetBuffer(bufHdr)); - if (buf_state & BM_VALID) - *foundPtr = true; - else - { - /* Previous read attempt must have failed; try again */ - *foundPtr = false; - } + *foundPtr = PinLocalBuffer(bufHdr, true); return bufHdr; } @@ -194,9 +175,7 @@ LocalBufferAlloc(SMgrRelation smgr, ForkNumber forkNum, BlockNumber blockNum, else { /* Found a usable buffer */ - LocalRefCount[b]++; - ResourceOwnerRememberBuffer(CurrentResourceOwner, - BufferDescriptorGetBuffer(bufHdr)); + PinLocalBuffer(bufHdr, false); break; } } @@ -485,6 +464,48 @@ InitLocalBuffers(void) } /* + * XXX: We could have a slightly more efficient version of PinLocalBuffer() + * that does not support adjusting the usagecount - but so far it does not + * seem worth the trouble. + */ +bool +PinLocalBuffer(BufferDesc *buf_hdr, bool adjust_usagecount) +{ + uint32 buf_state; + Buffer buffer = BufferDescriptorGetBuffer(buf_hdr); + int bufid = -buffer - 1; + + buf_state = pg_atomic_read_u32(&buf_hdr->state); + + if (LocalRefCount[bufid] == 0) + { + if (adjust_usagecount && + BUF_STATE_GET_USAGECOUNT(buf_state) < BM_MAX_USAGE_COUNT) + { + buf_state += BUF_USAGECOUNT_ONE; + pg_atomic_unlocked_write_u32(&buf_hdr->state, buf_state); + } + } + LocalRefCount[bufid]++; + ResourceOwnerRememberBuffer(CurrentResourceOwner, + BufferDescriptorGetBuffer(buf_hdr)); + + return buf_state & BM_VALID; +} + +void +UnpinLocalBuffer(Buffer buffer) +{ + int buffid = -buffer - 1; + + Assert(BufferIsLocal(buffer)); + Assert(LocalRefCount[buffid] > 0); + + ResourceOwnerForgetBuffer(CurrentResourceOwner, buffer); + LocalRefCount[buffid]--; +} + +/* * GUC check_hook for temp_buffers */ bool diff --git a/src/include/storage/buf_internals.h b/src/include/storage/buf_internals.h index 2afb9bb3099..970d0090615 100644 --- a/src/include/storage/buf_internals.h +++ b/src/include/storage/buf_internals.h @@ -415,6 +415,8 @@ extern int BufTableInsert(BufferTag *tagPtr, uint32 hashcode, int buf_id); extern void BufTableDelete(BufferTag *tagPtr, uint32 hashcode); /* localbuf.c */ +extern bool PinLocalBuffer(BufferDesc *buf_hdr, bool adjust_usagecount); +extern void UnpinLocalBuffer(Buffer buffer); extern PrefetchBufferResult PrefetchLocalBuffer(SMgrRelation smgr, ForkNumber forkNum, BlockNumber blockNum); |